A fuel injection valve with a piezoelectric actuator is described in, for example, German Published Patent Application No. 195 00 706. In this fuel injection valve, the piezoelectric or magnetostrictive actuator controls a working piston that acts upon a stroke piston via a hydraulic path transformer. The stroke piston is connected in a positive-locking manner via a needle valve to a valve closing member provided on a spray-discharge opening. The piezoelectric or magnetostrictive actuator is thus connected via the hydraulic path transformer in a force-locking manner to the valve closing member. If a suitable electric voltage is applied to the actuator, it expands and displaces the working piston accordingly. Even a relatively small displacement of the working piston is transformed by the hydraulic path transformer into a significantly larger displacement of the stroke piston so that the valve closing member releases the spray-discharge opening with a suitable cross-section. A fuel injection valve of a similar construction type is also described in German Patent No 43 06 073. This publication describes a housing-side mounting of the actuator in a special spherical disk support which achieves in the case of a small non-parallelism of the actuator end, a full-surface abutment of the piezoelectric actuator on the pressure piston acted upon by it.
Conventional fuel injection valves have the disadvantage that the injection pressure is predetermined by the fuel pressure generated by the fuel pump in the fuel intake line and thus the available injection pressure is limited. Moreover, there is the disadvantage of a non-negligible mass inertia of the stroke piston, the needle valve and the valve closing member. The response time of the fuel injection valve is determined by the mass inertia of these elements.